Pressure-regulating device, transportation vehicle, and pressure difference-controlling unit

ABSTRACT

A pressure controlling apparatus controls a pressure in a container capable of storing a molten metal and supplying the molten metal to an outside using a pressure difference and includes: a supplying portion for supplying a compressed gas to be supplied to the container; a flow passage for supplying the compressed gas from the supplying portion to the container; a first switching valve, being inserted into the passage, capable of manually switching a first mode that enables the passage of the gas between the supplying portion side and the container side and a second mode that enables the passage of the gas between the container side and the outside; an exhausting portion for exhausting a gas from the container; and a second switching valve for switching a pressure applying mode for applying a pressure to the container and an exhausting mode for exhausting the gas from the container.

TECHNICAL FIELD

The present invention relates to a pressure controlling apparatus usedfor a system for supplying, for example, a molten metal to an outside ofa container storing the molten metal such as molten aluminum by applyingpressure to an inside thereof, a transporting vehicle and a unit forcontrolling the pressure difference.

BACKGROUND ART

In a factory where aluminum is molded using many die-casting machines,an aluminum material is often supplied not only from within the factorybut also from outside of the factory. In such a case, a containerstoring aluminum in a melt is carried from a factory on the materialsupply side to a factory on the molding side to supply to each of astoring furnace of the die-casting machines the material kept in themelt. As an embodiment, a system of applying pressure to an inside ofthe container and supplying a molten metal from the container to thestoring furnace using a pressure difference is recommended (for example,Japanese laid-open utility model application publication H03-31063(first drawing)).

The technology according to the publication mentioned above isstructured such that the supply of molten aluminum from the container tothe storing furnace side starts as pressure is being increased and whenthe supply is stopped later, the supply of the gas from the outside tothe inside is switched to exhaust inside of the container, in order tohave pressure in the container to become at a state of the atmosphericpressure (page 10 line 7 to line 11 of Japanese laid-open utility modelapplication publication H03-31063).

As the container of this kind stores a molten metal of extremely hightemperature, the possibility of having to shutdown the process ofapplying pressure to the container for some reasons in an emergency isvery high. According to the publication, it is possible to cope withsuch emergency shutdown by switching from supplying gas to exhaustinggas.

Nevertheless, in an unexpected event where the switching did notfunction properly due to electronic trouble and the like caused by noisein the factory, or exhaustion was not performed, there is a very highrisk of inducing a serious accident. For this reason, providing, forexample, a manually operated valve open to the atmosphere and a valvefor blocking the flow passage and manually operate these valves in theevent of an emergency may be considered. However, there is a problemthat, in such case, switching operation of the two valves is required.

Furthermore, according to the above publication, pressure is applied toinside of the container by a gas supply device mounted on a forklift.

Nevertheless, there is a problem that with such gas supply device,inside of the container cannot be applied with steady pressure.

In such case, for example, compressed gas supplied from pipes runninginside the factory may be used. However in that case the containerplaced on a vehicle such as forklift has to be connected to the factoryside through a pipe, which has a negative effect on operability.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a pressure controllingapparatus that is capable of shutting down application of pressure tothe container and supply of the molten metal from the container to theoutside in an emergency with a very simple operation and, in the sametime, without fail.

In addition, an object of the present invention is to provide a unit forcontrolling pressure difference capable of steadily applying pressure tothe inside of the container without negatively affecting operability anda transporting vehicle.

Furthermore, an object of the present invention is to provide atransporting vehicle and a unit for controlling pressure difference thatis efficient and small in size. Especially, an object of the presentinvention is to provide a technology that uses a little amount ofcompressed gas and consumes little energy. Additionally, an object ofthe present invention is to provide a technology with a small number ofreplenishment of the compressed gas and with an excellent operability.

To solve the problem, the main object of the present invention is toprovide a pressure controlling apparatus for controlling a pressure in acontainer capable of storing a molten metal and supplying the moltenmetal to an outside using a pressure difference comprises, a supplyingportion for supplying a compressed gas to be supplied to the container,a flow passage for supplying the compressed gas from the supplyingportion to the container and a first switching valve, being insertedinto the passage, capable of manually switching a first mode thatenables the passage of the gas between the supplying portion side andthe container side and a second mode that enables the passage of the gasbetween the container side and the outside.

In the present invention, in a case where applying pressure to theinside of the container is to be shutdown in an emergency, the firstvalve is manually switched from the first mode to the second mode. Withsuch configuration, inside of the container can be released to theatmosphere, in the same time as the application of pressure to theinside of the container is stopped. This makes it possible to stop theapplication of pressure to the container 100 with more reliability in anemergency, and with a very simple operation. In other words, accordingto the pressure controlling apparatus of the present invention, thefirst mode and the second mode can be switched from one mode to theother exclusively with one same operation, which is very effective whenthe supply of the molten metal is to be stopped in an emergency. Forthis reason, due to the present invention safety, stability andreliability of the system can be improved. Of course, the supply of themolten metal may be stopped any time other than in emergency using thestructure of the present invention. In addition, since the firstswitching valve of the present invention can be structured, for example,with a three-way valve, the number of parts can be reduced.

The above-described supplying portion is, for example, a tank forstoring the compressed gas mounted on a transporting vehicle equippedwith a pressure controlling apparatus, and a flow passage and the likeconnected to a tank for supplying compressed gas on the factory side.Further, a compressor may be connected to the above-described tank. Ofcourse the compressor may be mounted on the transporting vehiclementioned above. In such case, the compressor may be supplied withelectricity from a dynamo of the transporting vehicle. Additionally,when the transporting vehicle is driven with the battery as well, thecompressor may be supplied with electricity from the battery.

The flow passage of the present invention can be, for example, an airtube, air hose and the like.

According to the pressure controlling apparatus of the presentinvention, a valve open to the atmosphere connected to the flow passage(i.e. inserted between the flow passage and the valve open to theatmosphere) and a controlling means for controlling the opening andclosing of the valve may be provided. The valve open to the atmosphereand the controlling means are structured differently from the emergencyshutdown means for shutting down the application of pressure to theinside of the container.

A transporting vehicle for mounting a pressure controlling apparatus ofthe present invention as described above comprises a part of flowpassage being a flexible air tube having a connecting portion forconnecting with the container. At the end of the air tube, a secondjoint portion that is detachably connected with the first joint portionprovided to the container is provided. The vehicle preferably becomprised further of a fork portion capable of inserting into andpulling out from a pair of channel member provided on a back side of thebottom of the container.

Therefore, one transporting vehicle mounted with the pressurecontrolling apparatus of the present invention can transfer a pluralityof containers and can supply molten metal to a plurality of use points.The present invention differs from the system of the above referencedpublication in which the container and the vehicle are integrated fromthat point of view.

A pressure controlling apparatus of the present invention comprises, anexhausting portion for exhausting a gas from the container, a secondswitching valve for switching pressure applying mode for applying apressure to the container and an exhausting mode for exhausting the gasfrom the container. The flow passage includes a first path forconnecting the supplying portion and the second switching valve, asecond path for connecting the exhausting portion and the secondswitching valve, a third path connecting the second switching valvethrough to the container side. The first switching valve may be insertedinto the third path.

Here, the exhausting portion may be, for example, a vacuum pump mountedon the transporting vehicle, also may be an interface portion providedfor being connected with the exhaustion facility in the factory.

The body of the switching valve is generally made of resins, however,there occurs a problem when being used in a system such as treatingmolten metals in which the valve is exposed to an environment oftemperature being as high as 700 degrees Celsius. In other words,temperature of the compressed gas in the container is very high due tothe heat from the molten metal, and when the compressed gas is to bereleased, the valve is likely to be thermally damaged thus thereliability may be questioned. Especially, the reliability is a seriousproblem for valves relating to safety, such as the leak valve and therelief valve. Therefore, from the point of view of reliability and thecost, it is desirable not to have valves open to the atmosphere in thecontainer, however, a container without a safety valve can be dangerous.Such kind of danger can be avoided at an utmost by adopting theswitching valve of the present invention. In addition, the safety caneven be improved in a new system of providing a valve open to theatmosphere to a pressure controlling apparatus side not on the containerside.

Another aspect of the present invention is a transporting vehicle fortransporting a container capable of storing a molten metal and supplyingthe molten metal to an outside using a pressure difference comprises anengine for driving the vehicle, a generator driven by the engine, acompressor driven by an electricity generated by the generator, a tankfor storing a compressed gas compressed by the compressor and a pressurecontrolling portion, having an interface portion detachably disposedagainst the container, for applying a pressure in the container via theinterface portion.

Yet another aspect of the present invention is a transporting vehiclefor transporting a container capable of storing a molten metal andsupplying the molten metal to an outside using a pressure differencecomprises a motor for driving the vehicle, a battery for supplying anelectricity to the motor, a compressor driven by the electricity in thebattery, a tank for storing a compressed gas compressed by thecompressor and a pressure controlling portion, having an interfaceportion detachably disposed against the container, for applying apressure in the container via the interface portion. According to thepresent invention, for example, a generator is driven by an enginemounted on the transporting vehicle while being run and/or idled and thegenerated electricity is used to drive the compressor and the compressedgas is stored in a tank. Alternatively, the gas compressed by thecompressor driven by the battery for supplying electricity to a motorfor running the vehicle is stored in the tank. Then, an interfaceportion provided at a tip of the air tube leading to the tank isconnected to the container, and inside the container is applied withpressure from the tank through the air tube, having the molten metalstored in the container flow to an outside.

According to the present invention, since the gas is compressed by thecompressor and temporarily stored in the tank, the tank plays a role of,so-called a “buffer” between the compressor and the container. For thisreason, the pressure can be applied to inside of the container steadily.In addition, since all the means for applying pressure is designed sothat it is being on the transporting vehicle, the vehicle independentlyfunctions as an apparatus for applying pressure. With thisconfiguration, it becomes not necessary, for example, to be connectedwith pipes flowing the compressed gas therein in the factory, and theoperability improves.

In addition, the present invention can be applied not only to a vehicledriven by gasoline but also to a vehicle driven by an electricitydriven, so-called, a “hybrid”.

A transporting vehicle of the present invention may be disposed with afilter on a line connecting between the compressor and the tank. Thefilter preferably catches a fragment of aluminum or moisture in thefluid. The filter is usually provided to prevent particles and the likefrom flowing to the container side. Especially, as the filter catchesthe moisture, the dried gas can be supplied to the container side, andthe safety can be improved.

A transporting vehicle according to the present invention may bedisposed with a first check valve that regulates the flow of gas fromthe tank to the compressor. By regulating the flow of gas from the tankto the compressor using the first check valve, pressure is not appliedto the compressor from the tank side, decreasing the load of thecompressor. With this configuration, the compressor can be made smaller.In addition, due to the first check valve, the particles do not flow tothe opposite direction, i.e. to the compressor side. The first checkvalve is preferably provided between the filter and the compressor. Withthis configuration, the particles and the like do not flow to the tankside or to the compressor side.

An transporting vehicle according to the present invention, may becomprised of means for measuring pressure in the tank and means forcontrolling start and stop of the compressor according to the measuredpressure as well as releasing the pressure between the compressor andthe first check valve to the atmospheric pressure before starting up thecompressor.

For example, the pressure release controlling device has a function ofthe measuring means and the controlling means described as above.

As controlling the start and the stop of the compressor according to thepressure in the tank, the pressure in the tank can be kept constant.With this configuration, the pressure can be applied to inside of thecontainer steadily. In addition, since the pressure between thecompressor and the first check valve is released to atmospheric pressurebefore activating the compressor, i.e. upon activating the compressor,the compressor can be started with less power. When one tries to startthe compressor from the state of it being applied with pressure, thecompressor initially needs extra power to resist to the applied pressurethat causes the compressor to become larger in size. In contrast, in thepresent invention, because the power necessary to start the compressorcan be made small, the compressor can also be made small. For example, afunction of releasing pressure to atmospheric pressure as describedabove can be realized as the controlling means has at least one valveand one end of which is connected to the atmospheric pressure and theother end is connected to the line between the first check valve and thecompressor.

According to the transporting vehicle of the present invention, it ispreferable that the container has a hatch capable of being opened andclosed on a top surface of the container and the interface portion isdetachably provided against the hatch.

In the present invention, because the interface portion is detachablyprovided against the hatch, the adhesion of the molten metal at amounting position of the interface portion in the backside of the hatchcan be checked every time the molten metal is being supplied in thecontainer. This makes it possible to prevent clogging of the portionbeforehand.

Yet another aspect of the present invention is a transporting vehiclefor transporting a container capable of storing a molten metal andsupplying the molten metal to an outside using a pressure differencecomprises a compressor, a tank for storing a compressed gas compressedby the compressor, an air tube, having an interface portion detachablydisposed against the container on one end and a first leak valvedisposed between the tank and the interface portion and on one of thefirst line and the third line, and a filter disposed between the firstleak valve and the interface portion.

Here, it is preferable to provide a second leak valve between the firstleak valve and the interface portion and the filter is preferablyprovided between the second leak valve and the air tube.

In the present invention, as valves of this kind is being fixed betweenthe tank and the interface portion, the damage of the valves caused bythe heat and the like and deterioration of the valve can be prevented,so that the molten metal can be treated more safely. Additionally, thevalve and the like do not have to be provided by each container,therefore the number of parts for the container can be reduced.Moreover, in the present invention, since the filter is provided betweenthe first leak valve and the interface portion, the first leak valvebeing stuck caused by particles and the like from the container sidedoes not occur any more. Therefore the leakage of pressure can beprevented. In addition, the leakage of pressure can be prevented moreeffectively by providing a filter, for example, a strainer right infront of the first leak valve.

Another aspect of the present invention is a transporting vehicle fortransporting a container capable of storing a molten metal and supplyingthe molten metal to an outside using a pressure difference, comprises acompressor, a tank for storing a compressed gas compressed by thecompressor, a vacuum pump, an air tube, having an interface portiondetachably disposed against the container on one end, a switchingportion switching a flow passage leading to the tank and a flow passageleading to the vacuum pump and a pipe disposed between the switchingportion and the other end of the air tube.

In the present invention, the vacuum pump as means for decreasingpressure is designed to be mounted on the vehicle, the vehicleindependently functions as an apparatus for increasing and decreasingpressure. Therefore, for example, not only connection with pipes for thecompressed gas becomes unnecessary in the factory, but also connectionwith pipes provided for vacuuming also becomes unnecessary. In summary,the vehicle and the container enable independent supply of the moltenmetal from outside and also supply of the molten metal from thecontainer to the outside. In addition, according to the presentinvention, since a common air tube is used in both application andreduction of pressure, the number of parts can be decreased as well.

The transporting vehicle according to the present invention ispreferably further comprised of a first leak valve disposed between thetank and the interface portion and a filter disposed between the firstleak valve and the interface portion. Moreover, the transporting vehicleaccording to the present invention is preferably further comprised of asecond leak valve disposed between the switching portion and one end ofthe air tube and a filter disposed between the second leak valve and theair tube.

Yet another aspect of the present invention is a pressure differencecontrolling unit being mounted on a transporting vehicle holding acontainer capable of storing a molten metal and supplying the moltenmetal to an outside using a pressure difference, comprises a compressor,a tank for storing a compressed gas compressed by the compressor and apressure controlling portion, having an interface portion detachablydisposed against the container, for applying a pressure in the containervia the interface portion with the compressed gas.

A constant pressure can be applied to the inside of the containerwithout negatively affecting the operability by disposing the pressuredifference controlling unit according to the present invention on atransporting vehicle such as a forklift and the like and by using theabove-described container.

The pressure difference controlling unit of the present invention isable to adopt the same structure as described above.

In other words, being provided with a filter disposed on a line betweenthe compressor and the tank and further being provided with a firstcheck valve disposed on the line between the tank and the interfaceportion regulating the gas flow from the tank to the compressor, thefirst check valve is being provided between the first check valve andthe compressor, further being provided with a second check valvedisposed on the line so that the filter is placed between the firstcheck valve and the second check valve, and also further comprised withmeans for measuring pressure in the tank and controlling means forcontrolling start and stop of the compressor and for releasing pressurebetween the compressor and the first check valve to an atmosphericpressure before start-up of the compressor, and said controlling meanshas at least one valve one end of which is connected to the atmosphericpressure and the other end is connected to the line between the firstcheck valve and the compressor etc.

The pressure difference controlling unit of the present invention ispreferably driven by a mono-layer electricity. With this configuration,the electricity supply system can be made smaller compared with that of“three phase types”.

The present invention described above is the one with a tank, however, ablower may be used as a source of applying pressure to the containerinstead of a tank. When smaller sized transporting vehicle is requiredconsidering the size and running space of the transporting vehicle, ablower may be used instead of a tank. Both the blower and the tank maysurely be used.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a front view showing the structure of a transporting vehicleaccording to one embodiment of the present invention.

FIG. 2 is a plane view of the transporting vehicle shown in FIG. 1.

FIG. 3 is a diagram showing a structure of the pressure differencecontrolling apparatus according to one embodiment of the presentinvention.

FIG. 4 is a diagram showing the structure of the pressure differencecontrolling apparatus in relation to a forklift and a containeraccording to one embodiment of the present invention;

FIG. 5 is a diagram showing a structure of a leak valve according to anembodiment of the present invention.

FIG. 6 is a diagram showing a structure of a typical leak valve of theprior art.

FIG. 7 is a diagram showing a structure of an emergency shutdown portionaccording to an embodiment of the present invention.

FIG. 8 is a cross-sectional view of the emergency shutdown portion of afirst mode (under normal operation).

FIG. 9 is a cross-sectional view of the emergency shutdown portion of asecond mode (under emergency shutdown).

FIG. 10 is a cross-sectional view of the container according to anembodiment of the present invention.

FIG. 11 is a plane view of the container shown in FIG. 10.

FIG. 12 is a cross sectional view of FIG. 10 cut at A-A line.

FIG. 13 is a schematic diagram showing the configuration of a metalsupply system according to an embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described withreference to the drawings.

FIG. 1 is a side view showing the structure of a transporting vehicleaccording to one embodiment of the present invention. FIG. 2 is a planeview thereof.

The transporting vehicle 1 is basically a forklift. The transportingvehicle 1 has a driving seat 2 provided almost center of the vehicle, afork portion 3 provided at the front of the vehicle and a pressurecontrolling apparatus 4 provided on the top of the vehicle 1.

The pressure controlling apparatus 4 has two receiver tanks 5 forstoring gas to be supplied for applying pressure to the inside of thecontainer 100, an a compressor 6 for supplying the gas to be compressedto the receiver tank, a vacuum pump 7 for reducing the pressure in thecontainer 100, a filter 8 and an emergency shutdown portion 9.

The emergency shutdown portion 9 is disposed at a front and one side ofthe driving seat 2. With this configuration, a driver seated at thedriving seat can access to a lever 10 for shutting down the operation inan emergency provided at the emergency shutdown portion 9.

The emergency shutdown portion 9 is inserted between a pipe 11 insidethe pressure controlling apparatus 4 and an air tube 12. The gas usedfor applying pressure to inside of the container is discharged from atip of the air tube 12 through the pipe 11, emergency shutdown portion 9and the air tube 12.

At the tip of the air tube 12, a joint portion 14 is detachably disposedagainst a joint portion 13 provided in the container 100. Then the jointportion 14 of the tip of the air tube 12 is connected to the jointportion 13 in the container 100 and inside of the container 100 can beapplied with pressure by supplying the gas to the inside of thecontainer 100 from the receiver tank 5 through the air tube 12.Similarly, the joint portion 14 of the tip of the air tube 12 isconnected to the joint portion 13 in the container 100 and the pressurein the container 100 can be decreased using a vacuum pump 7 of thepressure controlling apparatus 4 through the air tube 12. As a materialfor the air tube 12, for example, a synthetic resin such as rubber or ametal can be used. The material is preferably heat resistant since theair tube is positioned close to the container 100 bearing hightemperature.

A fork portion 3 has a fork 15 detachably disposed against a pair of achannel member 171 which is provided at the back of the bottom portionof the container 100 and an ascending and descending mechanism 16 forascending and descending the fork 15.

FIG. 3 is a diagram showing a structure of a pressure controllingapparatus.

As shown in FIG. 3, the pressure controlling apparatus 4 has at least anelectric generator 18 driven by an engine 17 for driving thetransporting vehicle 1 which causes the vehicle to run or idle and acompressor 6 driven by the generated electricity. When the transportingvehicle 1 is driven using a battery and a motor, the compressor 6 isdriven using the battery, in which case, the compressor can be operatedindependently from running or idling of the vehicle.

Then, the gas used for applying pressure to the inside of the containercompressed by the compressor 6 is stored in the receiver tank 5. Inother words, the compressed gas is stored in the receiver tank 5 fromthe compressor 6 while the transporting vehicle 1 is running or idling.Therefore, the receiver tank 5 is configured as, so called “a buffer”,between the compressor 6 and the container 100. With this structure,when the molten metal is supplied from the container 100 to an outside,an inside of the container 100 can be applied with a constant pressure.In addition, the gas can constantly be charged to the receiver tank 5enabling the supply of the molten metal to the outside to be performedflexibly, anytime, anywhere.

Applying constant pressure to the inside of the container is extremelyimportant according to the understanding of the inventors and the likeof the present invention. When the pressure applied to the inside of thecontainer 100 is unstable, often there occurs the case where the moltenmetal containing gas suddenly gushes out from the tip of the pipe 144 ofthe container 100, spattering the molten metal to its surroundings. Inaddition, by providing the receiver 5, the capacity of the compressor 6may be small. Therefore the compressor 6 with a small amount ofelectricity consumption and small in its size can be used.

A first check valve 20, a line filter 8 a, an gas drier 8 b and a secondcheck valve 21 are provided on the pipe 19 between the compressor 6 andthe receiver tank 5 disposed in consecutive order from the compressor 6side. Both of the first check valve 20 and the second check valve 21 areprovided to prevent reversal flow of the gas from the receiver tank 5side to the compressor 6 side. The first check valve 20, for example,prevents the reverse flow of the gas from the line filter 8 a and thegas drier 8 b side to the compressor 6, and especially preferable to beprovided close to the line filter 8 a. With such configuration, the pipe19 a between the compressor 6 and the line filter 8 a can be preventedeffectively from becoming dirty and/or being stuck.

The line filter 8 a is a filter for removing moisture and grease fromthe gas supplied from the compressor 6 to the receiver tank 5. The gasdrier 8 b is a filter for drying the gas supplied from the compressor 6to the receiver tank 5.

The second check valve 21 is provided to prevent the reverse flow of thegas from the receiver tank 5 side to the compressor 6. A pressurerelease controlling device 22 is connected to the pipe 19 b disposedbetween the receiver tank 5 and the second check valve 21.

The pressure release controlling device 22 has a pressure sensor 23 anda CPU 24. The pressure sensor 23 detects pressure in the receiver tank 5and controls “ON” and “OFF” of the compressor 6 based on the detectedresult. For example, the compressor 6 is turned ON when the pressure inthe receiver tank 5 is lower than a predetermined value. On the otherhand, the compressor 6 is turned OFF when the pressure in the receivertank 5 is higher than the predetermined value.

A pipe 19 c is connected to the pipe 19 a disposed between thecompressor 6 and the first check valve 20. One end of the pipe 19 c isreleased to an atmosphere through a leak valve 25. Opening and closingof the leak valve 25 is controlled by the CPU 24 of the pressure releasecontrolling device 22.

The CPU 24 opens the leak valve 25 from its closed state before turningon the compressor 6 when the pressure in the receiver tank 5 is lowerthan the predetermined value. This causes the pressure in the pipe 19 adisposed between the compressor 6 and the first contact valve 20 toreturn to an atmospheric pressure. Then the CPU 24 turns on thecompressor 6 and closes the leak valve 25 after a predetermined time.Having pressure in the pipe 19 a to return temporarily to theatmospheric pressure, the compressor 6 can be started-up with lessenergy, enabling reduction in size of the compressor 6.

In the present invention, the pipe on the upstream side of the receivertank 5 is narrower compared to the downstream side (i.e. the side closerto the container 100), for example, the diameter of the pipe at upstreamside is narrower by two-third. This is because while large amount of thecompressed gas is released at once from the receiver tank 5 to thecontainer 100, the gas is released gradually from the compressor 6 tothe receiver tank 5. In other words, the flow rate of the gas betweenthe receiver tank 5 and the container 100 differs greatly from the flowrate of the gas between the compressor 6 and the receiver tank 5.

Then, in the present invention, the line filter 8 a and the gas drier 8b can be reduced in size as being provided to the upstream side of thereceiver tank 5, not the downstream side thereof, namely, in the pipe 19disposed between the receiver tank 5 and the compressor 6, where thepipe being narrower and has smaller flow rate.

The receiver tank 5 is connected to a pipe 26 for compressed gas and thepipe 26 is connected to a switching valve 27 comprised of, for example,a three-way valve. In addition, the vacuum pump 7 is connected to a pipe28 for vacuum pumping and the pipe 28 is connected to the switchingvalve 27. The switching valve 27 switches the connection between thepipe 26 for the compressed gas and the air tube 12 side, and theconnection between the air tube 12 side and the pipe 28 for vacuumpumping. The switching valve 27 is connected to the tip of the air tube12 through a pressure gauge 29, a relief valve 30, a leak valve 31 andthe emergency shutdown portion 9.

An electronic pressure control valve 32 and the leak valve 33 areconnected to the pipe 26 for compressed gas on the pressure receivertank 5 side (upstream side). An electronic pressure control valve 34 andthe leak valve 35 are connected to the pipe 28 for vacuum pumping on thevacuum pump 7 side (downstream side).

Each of the electronic pressure control valve 32 and the electronicpressure control valve 34 is designed to control pressure in the pipe 26for compressed gas and the pipe 28 for vacuum pumping.

The filter 51 prevents dust and the like to enter into (the filter) theemergency shutdown portion 9 from the container 100 side. The problem ofthis kind occurs especially often when supply of the molten metal isstopped, namely when the pressure returns from an increased pressurestate to the atmospheric pressure. The filter 51 may be provided on thecontainer 100, however, in that case, the filter needs to be provided toevery container 100. In the present invention, the number of filters tobe used and time consuming maintenance operation can be reduced, as thefilter 51 is provided on the transporting vehicle 1 side.

According to the knowledge of the inventors of the present invention,amount of dust and dirt transmitted from the container side to thereceiver tank 5 side is much larger compared to the amount of dust anddirt from the receiver tank 5 side to the container side. In the presentinvention, providing the filter 51 on the downstream side of the valvesand the emergency shutdown portion 9 enables to prevent the relief valve30 and other valves from being stuck caused by dirt and dust transmittedfrom the container 100 side. However, the filter 51 may be disposed onthe upstream side, or alternatively a plurality of filters may also bedisposed in a plurality of places. For example, the filter 51 may beprovided between the switching valve 27 and the relief valve 30 and thefilter 31 may be provided between the switching valve 27 and the leakvalve 33.

An electric control board electronically controls these electronicpressure control valve and the valve system (not shown). The pressuredifference between inside of the container 100 and outside can beadjusted by manipulating a controlling panel (not shown) provided closeto the driver.

FIG. 4 is a diagram explaining another embodiment of the presentinvention. In this example, a blower 6 b is used as a pressure sourceinstead of the compressor 6 and the system is structured as such thatthe compressed gas is provided to the container 100 side without usingthe receiver tank 5. With this configuration, the pressure controllingapparatus 4 can be reduced in size. When the transporting vehicle 1 is abattery car, the electricity of the blower 6 b may be obtained from thebattery.

FIG. 5 is a diagram showing a preferable embodiment of the leak valve33. As shown in FIG. 5, in this embodiment, a strainer 33 a is insertedin the position immediately before the leak valve 33. As shown in FIG.6, when a strainer such as the strainer 33 is not inserted, the leakvalve 33 is clogged with an object 33 b, such as pieces of aluminum orfire refractory materials and the like transmitted from the container100 side. As a result, the valve does not close, which may causepressure leakage and may affect stopping operation of the supply of themolten metal. In contrast, according to the present invention, becauseof the inserted strainer 33 a, the pressure leakage can be prevented andsafe stopping operation can be realized.

Next, the emergency shutdown portion 9 will be described.

FIG. 7 is an enlarged diagram of an emergency shutdown portion 9, FIG. 8is a state of normal operation (not at an emergency shutdown state), andFIG. 9 is a sectional view of the emergency shutdown portion 9.

As shown in FIG. 7 the emergency shutdown portion 9 is comprised of apipe 38 that stretches from an upper portion to downward (the firstportion 36) and bends to the driving seat side at a lower portion (thesecond portion 37). The upper end portion 39 of the pipe 38 is connectedto the pipe 11 and the other end 40 is connected to the air tube 12.

A three-way valve 41, one embodiment of a switching valve, is insertedinto the second portion 37 of the pipe 38. A first valve opening 42 ofthe three-way valve 41 is connected to the pipe 11, a second valveopening 43 is connected to the air tube 12 and a third valve opening 44is open to atmosphere. The three-way valve 41 can be switched betweenthe first mode and the second mode by manually rotating the lever 10.The first mode enables the flow of the gas between the first valveopening 42 and the second valve opening 43 and the second mode enablesthe flow of the gas between the second valve opening 43 and a thirdvalve opening 44.

In the present invention, for example, in a case where application ofpressure is to be stopped because the receiving side of the molten metalis about to overflow, the three-way valve as a switching valve ismanually switched from the first mode to the second mode. With thisoperation the application of pressure into the container 100 is stoppedand, in the same time, the inside of the container 100 is released toatmosphere. Therefore the application of pressure to the container 100can be stopped certainly in an emergency, and with a very simpleoperation. In other words, according to the present invention, the firstmode and the second mode can be switched from one mode to the otherexclusively with one same operation, which is very effective at the timeof emergency shutdown.

In addition, since the switching valve of the present invention, can bestructured, for example, with a three-way valve, the number of parts canbe reduced.

A pipe 45 with its end being open to atmosphere is connected the thirdvalve opening 44. The lower part of the pipe 45 is connected to thethird valve opening 44, stretching from the lower portion to the upperportion, and at the upper portion, stretching horizontally to anopposite side of the driving seat. The pipe 38 crosses the first portion36 and the pipe 38.

At the end of the pipe 45, a joint portion 46 detachably connected tothe joint portion 14 of the air tube 12 is provided. When the air tube12 is not connected to the container 100, the joint portion 14 at theend of the air tube 12 is connected to the joint portion 46 of the pipe45 so that the air tube 12 can be placed in order. In addition, the airtube can be prevented from flapping when the compressed gas is beingsupplied.

As shown in FIG. 8, the three-way valve of the emergency shutdownportion 9 is designed to be at the first mode under a normal operation.This configuration allows gas to flow between the first valve opening 42and the second valve opening 44, therefore, supplying gas for applyingpressure to the inside of the container and reducing the pressure in thecontainer 100 using the vacuum pump 7 through the air tube 12 becomepossible.

Then, for example, when emergency shutdown operation becomes necessarywhile the gas used for applying pressure to the inside of the container100 is being supplied from the receiver tank 5, the lever 10 is turnedand the three-way valve 41 is switched to the second mode. With thisconfiguration, a flow passage to the first valve opening 42 from thethree-way valve 41 is blocked so that the supply of the gas used forapplying pressure to the inside of the container 100 from the receivertank 5 is stopped. In the same time, the flow of the gas becomespossible between the second valve opening 43 and the third valve opening44 that is release to the atmosphere. With this configuration, theinside of the container 100 is released to the atmosphere. In otherwords, in the present invention, at a time of emergency, the supply ofgas used for applying pressure to the inside of the container 100 can bestopped and, in the same time, inside of the container is released tothe atmosphere with one same operation, namely, manually turning thelever 10 provided close to the driving seat, which leads to a high levelof safety. Similarly, when the pressure in the container 100 is beingreduced using the vacuum pump 7, decreasing the pressure in thecontainer 100 is stopped and, in the same time, inside of the containeris released to the atmosphere with a single action, namely, manuallyturning above-mentioned lever 10.

Next, an example of the container used in another embodiment will bedescribed.

FIG. 10 is a cross-sectional view of the container, and FIG. 11 is aplane view thereof. The container 100 is configured such that a largelid 152 is provided at an upper opening 151 of a bottomed cylindricalbody 150. Flanges 153 and 154 are provided at outer peripheries of thebody 150 and the large lid 151 respectively, so that the flanges arefastened together with bolts 155 to fix the large lid 151 to the body150. It should be noted that the outside of the body 150 and the largelid 151 is made of, for example, metal and the inside thereof is made ofrefractories, with a heat insulator being inserted between the metalframe and the refractory material.

At one point on the outer periphery of the body 150, a pipe attachmentportion 158 is provided which is provided with a flow path 157 startingfrom the inside of the body 150 and communicating with the pipe 144.

Here, FIG. 12 is a cross-sectional view taken along a line A-A acrossthe pipe attachment portion 158 shown in FIG. 10.

As shown in FIG. 12, the outside of the container 100 is constituted ofa metal frame 100 a, and the inside thereof is constituted of arefractory member (the first lining) 100 b, with a heat insulatingmember which has a smaller heat conductivity (the second lining) 100 cbeing inserted between the frame 100 a and the refractory member 100 b.Besides, the flow path 157 is formed to be sheathed in the refractorymember 100 b, which is provided on the of the container 100. In otherwords, the flow path 157 is provided in the refractory member 100 bsfrom a position close to the bottom and inside of the container 100, toan exposed portion of an upper surface of the refractory member 100 b.With this configuration, the flow path 157 is separated from “inside” ofthe container by a refractory member with large heat conductivity. Theadoption of such configuration enables the released heat to betransmitted to the flow passage. A heat insulating member is disposed onthe outside of the refractory member, outside of the flow path (oppositeto the container side). The refractory member with higher density andbetter heat conductivity than heat insulator is used. As a refractorymember a fire resistant type ceramic material can be named as anexample. As a heat insulator a heat insulating type ceramic materialsuch as heat insulating caster and a board material can be named.

The flow path 157 in the pipe attachment portion 158 extends toward anupper portion 157 b on the outer periphery of the body 150, through anopening 157 a provided at a position on the inner periphery of the body150 close to a bottom portion 150 a of the container body. The pipe 144is fixed to communicate with the flow path 157 in the pipe attachmentportion 158. One end portion 159 of the pipe 144 faces downward.

In addition, around the pipe 144 close to the pipe attachment portion158, a heat insulator 44 a is disposed to surround the pipe 144. Withthis configuration, the pipe 144 side absorbs heat in the flow path 157side and the decrease in temperature on the flow path 157 side can beprevented as much as possible. Especially, the molten metal is likely tobe cooled off around the pipe 144 close to the pipe attachment portion158 and also, being a position where the liquid surface sways at a timeof transporting the container, the molten metal often solidifies. Thesolidification of the molten metal can be prevented at this position bysurrounding the pipe 144 with the heat insulator 44 a.

The flow path 157 and the pipe 144 linking thereto are preferably almostthe same in inner diameter, about 65 mm to about 85 mm. Conventionally,this kind of pipe has been about 50 mm in inner diameter. This isbecause large pressure used to be considered necessary when supplyingthe molten metal from the pipe by applying pressure to the inside of thecontainer. In contrast, the inventors and the like of the presentinvention concludes that the inside diameter of the pipe 144 ispreferable to be of much larger than 50 mm, namely, 65 mm to 85 mm, morepreferable to be 70 mm to 80 mm, and even more preferable to be 70 mm.In other words, two parameters, weight of the molten metal in the pipeitself and viscosity resistance of the inside wall of the pipe and theflow path are considered to have a great effect on the resistance thatprevents the molten metal from flowing inside the flow path and the pipeto the upper direction. Here, when inside diameter is smaller than 65mm, the molten metal flowing in the flow path is affected from both theweight of the molten metal itself and the viscosity resistance of theinside wall, however, when inside diameter is larger than 65 mm the areathat is not affected from the viscosity resistance of the inside wallemerges from almost the center of the flow and such area graduallyspreads. The effect of this area is so large that the resistance thatprevents the flow of the molten metal starts to decrease. Therefore,application of a very small pressure in the container is sufficient tosupply the molten metal therefrom. In summary, conventionally theexistence of such area has not been considered and only the weight ofthe molten metal itself is used to be regarded as a variable of theresistance that prevents the flow of the molten metal and the insidediameter is used to be around 50 mm from operability and the maintenancepoint of view. On the other hand, when inside diameter is over 85 mm,the weight of the molten metal as a resistance preventing the flowbecomes prevalent resulting in large resistance against the flow of themolten metal. According to the prototype produced by the inventors ofthe present invention and the like, when inside diameter being 70 mm to80 mm, a very small pressure is sufficient to be applied to inside ofthe container. Especially, inside diameter being 70 mm is mostpreferable, from a point of view both the standardization and theoperability. This is because the diameter of a pipe is standardized by10 mm, namely, 50 mm, 60 mm, 70 mm etc and smaller the diameter, theeasier to handle and the better the operability.

By having the diameter of the pipe to be as described above, thepressure necessary for the supply of the molten metal may be decreased.This indicates that using a container of this kind enables to shortenthe time of the molten metal being at stand still without decreasing theamount of supplied molten metal per a unit time. For example, in a casewhere inside of the container is open to atmosphere through, forexample, the leak valve 28 and the emergency shutdown portion 9, thesmaller the applied pressure (i.e. the smaller the pressure in thecontainer) the shorter the time consumed to return to the atmosphericpressure. Even when the application of the pressure is stopped, themolten metal continues to be supplied to the outside unless the pressurein the container is released. Using a pipe with above-described diameterenables to improve safety when stopping the supply.

At almost the center of the aforementioned large lid 152, an opening 160is provided, and a hatch 162 with a handle 161 attached thereto isdisposed at the opening 160. The hatch 162 is provided at a positionslightly higher than the upper face of the large lid 152. A portion onthe outer periphery of the hatch 162 is attached to the large lid 152through a hinge 163. This allows the hatch 162 to freely open and closethe opening 160 in the large lid 152. In addition, bolts with handles164 for fixing the hatch 162 to the large lid 152 are attached to twopoints of the outer periphery of the hatch 162 in a manner opposite tothe position to which the hinge 163 is attached. By closing the opening160 in the large lid 152 with the hatch 162 and rotating the bolts withhandles 164, the hatch 162 is fixed to the large lid 152. On the otherhand, by inversely rotating the bolts with handles 164 to release thefixation, the hatch 162 can be opened from the opening 160 in the largelid 152. Then, with the hatch 162 opened, maintenance of the inside ofthe container 100 and insertion of a gas burner at the time ofpreheating can be performed through the opening 160.

Further, a through hole 165 for internal pressure adjustment forreducing and applying the pressure in the container 100 is provided atthe center or a position slightly off from the center of the hatch 162.To the through hole 165, a pipe 66 for applying and reducing thepressure is connected. The pipe 66 extends upward from the through hole165, bends at a predetermined height, and extends in the horizontaldirection. The surface of a portion of the pipe 66 inserted into thethrough hole 165 is threaded, and on the other hand, the through hole165 is also threaded. This firmly screws the pipe 66 to the through hole165.

An above-described joint portion 13 is provided at a tip of the pipe 66.Then, it is possible to introduce the molten aluminum into the container100 through the pipe 144 and the flow path 157 using a pressuredifference resulting from reducing the pressure, and it is possible tosupply the molten aluminum to the outside of the container 100 throughthe flow path 157 and the pipe 144 using a pressure difference resultingfrom applying the pressure. It should be noted that use of an inert gas,for example, nitrogen gas as the compressed gas makes it possible toprevent more effectively oxidation of the molten aluminum during thepressurization.

In this embodiment, while the through hole 165 for applying and reducingthe pressure is provided in the hatch 162 which is disposed at almostthe center portion of the large lid 152, the aforementioned pipe 66extends in the horizontal direction, thus making it possible to performsafely and easily the work of connecting the pipe 167 for applying orreducing the pressure to the pipe 66. Furthermore, the pipe 66 extendsin the horizontal direction as described above and thus can be rotatedwith respect to the through hole 165 by a small force, so that the pipe66 screwed to the through hole 165 can be fixed and removed by a verysmall force, for example, without using a tool.

Further, valves like relief valve, leak valve and other valves are notattached to the container 100 of the present invention. This is whatdiffers from structure of a conventional container.

In the large lid 152, two through holes 170 for level sensors aredisposed with a predetermined distance therebetween into which twoelectrodes 169 are detachably inserted as the level sensors. Theelectrodes 169 are inserted into the through holes 170 respectively. Theelectrodes 169 are disposed opposite to each other in the container 100,and their tips extend, for example, to positions at a level almost thesame as that of a maximum liquid surface of the molten metal in thecontainer 100. It is thus possible to detect the maximum level of themolten metal in the container 100 by monitoring the conduction statebetween the electrodes 169, thereby enabling prevention of excessivesupply of the molten metal to the container 100 with more reliability.

On the rear face of the bottom portion of the body 150, two channels 171having a cross section in a square shape into which, for example, a forkof the fork lift truck (not shown) is inserted and a predeterminedlength, are disposed, for example, in parallel to each other. Further,the entire bottom portion inside the body 150 is inclined to be low onthe flow path 157 side. This reduces so-called remained melt when themolten aluminum is supplied to the outside through the flow path 157 andthe pipe 144 by compression. In addition, when the container 100 istilted, for example, at the time of maintenance to pour the moltenaluminum to the outside through the flow path 157 and the pipe 144, theangle of tilting the container 100 can be decreased, providing improvedsafety and workability.

Therefore, in the container 100 of the present invention, since memberssuch as stalks which is constantly being exposed to the molten metalsdoes not have to be provided, there is no need to replace parts as such.In addition, since there is no member such as a stalk that hinderspreheating being disposed in the container 100, the operability forpreheating is improved and preheating can be performed effectively.Further, when the molten metal is stored in the container 100, anoperation such as scooping oxidized substances and the like on thesurface of the molten metal is necessary in many cases. When the stalkis disposed in the container, the operation is not easily performed,however, the container 100 has no structure such as a stalk being insidethe container 100, operability can be improved. Moreover, the flow path157 is structured to be located inside the refractory member 100 b ofhigh heat conductivity, the heat inside of the container 100 can easilybe transmitted to the flow path 157. For this reason, decrease intemperature of the molten metal flowing in the flow path 157 can beprevented as much as possible.

As described above, in the container 100 according to this embodiment,the through hole 165 for internal pressure control is provided in thehatch 162, and the pipe 66 for internal pressure adjustment is connectedto the through hole 165, so that attachment of metal to the through hole165 for internal pressure control can be checked every supply of themolten metal into the container 100. This makes it possible to preventclogging of the pipe 66 and the through hole 165 used for adjusting theinternal pressure.

Further, in the container 100 according to this embodiment, the throughhole 165 for internal pressure control is provided in the hatch 162, andadditionally the hatch 162 is provided at almost the center of the upperface portion of the container 100 corresponding to a position of themolten aluminum where the level of the melt changes and melt dropssplash off at a relatively rare, resulting in less attachment of themolten aluminum to the pipe 66 and the through hole 165 used foradjusting the internal pressure. This makes it possible to preventclogging of the pipe 66 and the through hole 165 used for adjusting theinternal pressure.

Further, in the container 100 according to this embodiment, the hatch162 is provided in the upper face portion of the large lid 152, so thatthe distance between the rear face of the hatch 162 and the liquidsurface is longer by the thickness of the large lid 152 than thedistance between the rear face of the large lid 152 and the liquidsurface. This reduces the possibility of aluminum attaching to the innerface of the hatch 162 provided with the through hole 165, making itpossible to prevent clogging of the pipe 66 and the through hole 165used for controlling the internal pressure.

Next, an embodiment of a metal supplying system in which thetransporting vehicle of the present invention is used will be described.

FIG. 13 is a diagram showing the entire configuration of a metal supplysystem according to an embodiment of the present invention.

As shown in the drawing, a first factory 210 and a second factory 220are provided at locations apart from each other across, for example, apublic road 230.

In the first factory 210, a plurality of die casting machines 211 arearranged as use points. Each of the die casting machines 211 moldsproducts in a desired shape by injection molding using molten aluminumas a raw material. The products can include, for example, parts relatingto an engine of an automobile and the like. Besides, the molten metal isnot limited only to an aluminum alloy, but alloys containing othermetals such as magnesium, titanium, and so on as main constituents arealso usable. Near the die casting machines 211, there are storingfurnaces (local storing furnaces) 212 that temporarily store moltenaluminum before shots. This local storing furnace 212 is designed tostore the molten aluminum for a plurality of shots, so that the moltenaluminum is injected from the storing furnace 212 into the die castingmachine 211 through a ladle 213 or a pipe for every shot. Further, eachof the storing furnaces 212 is provided with a level sensor (not shown)that detects the level of the molten aluminum stored in a container 100and a temperature sensor (not shown) that detects the temperature of themolten aluminum. Detection results by these sensors are passed to acontrol panel of each of the die casting machines 211 or a centralcontroller 216 in the first factory 210.

The container 100 received to the first factory 210 in the receivingstation is carried to a predetermined die casting machine 211 by thetransporting vehicle 1, and the molten aluminum is supplied to thestoring furnace 212 from the container 100. The container 100 finishedwith the supply is returned to the receiving portion again mounted onthe transporting vehicle 1.

In the first factory 210, a first furnace 219 is provided for meltingaluminum and supplying it to the container 100, and the container 100,being supplied with the molten aluminum from the first furnace 219, isalso delivered by the transporting vehicle 1 to a predetermined diecasting machine 211.

In the first factory 210, a display section 215 is disposed whichdisplays a fact that the die casting machines 211 demand for theadditional aluminum melt. More specifically, for example, a uniquenumber is given to every die casting machine 211 and displayed on thedisplay section 215, so that the number on the display section 215corresponding to the die casting machine 211 which needs addition of themolten aluminum is lighted up. Based on the display on the displaysection 215, an operator carries the container 100 to the die castingmachine 211 corresponding to the number using the transporting vehicle 1to supply the molten aluminum. The display on the display section 215 isperformed by a control of the central controller 216 based on thedetection result by the level sensor of the aluminum melt.

In the second factory 220, a second furnace 221 is provided for meltingaluminum and supplying it to the container 100. A plurality of types ofcontainers 100 are provided which are different in capacity, pipelength, height, width, and so on. For example, there is a plurality oftypes of containers 100 different in capacity in accordance with thecapacities or the like of the local storing furnaces 212 for the diecasting machines 211 in the first factory 210. The containers 100supplied with the molten aluminum from the second furnace 221 aremounted on a truck 232 for carriage by means of a forklift truck. Thetruck 232 transports the container 100 via the public road 230 to areceiving portion of the first factory. Besides, vacant containers 100placed in the receiving station are returned to the second factory 20 bythe truck 232.

In the second factory 220, a display section 222 is disposed whichstates a fact that the die casting machines 211 in the first factory 210call additional molten aluminum. The display section 222 is almost thesame in configuration as the display section 215 in the first factory210. The display on the display section 222 is performed by a control ofthe central controller 216 in the first factory 210, for example, via acommunication line 233. It should be noted that, out of the die castingmachines 211 which need supply of the molten aluminum, the die castingmachines 211, which are determined to be supplied with the moltenaluminum from the first furnace 219 in the first factory 210, aredisplayed in distinction from the other die casting machines 211 on thedisplay section 222 in the second factory 220. For example, it isdesigned to blink the numbers corresponding to the die casting machines211 determined as above. This can prevent the molten aluminum from beingsupplied by mistake from the second factory 220 side to the die castingmachines 211 which have been determined to be supplied with the moltenaluminum from the first furnace 219. Further, on this display section222, data transmitted from the central controller 216 is also displayedin addition to the above display.

Next, description will be made on the action of the metal supply systemconfigured as described above.

The central controller 216 monitors the amount of the molten aluminum ineach of the storing furnaces 212 through the level sensor provided ateach of the local storing furnaces 212. When there arises a demand forsupplying the molten aluminum to one of the storing furnace 212, thecentral controller 216 transmits to the second factory 220 side throughthe communication line 233 the “ID number” of the storing furnace 212,“temperature data” of the storing furnace 212 detected by thetemperature sensor provided at the storing furnace 212, “form data” onthe form of the storing furnace 212, final “time data” of the storingfurnace 212 running out of the molten aluminum, “traffic data” of thepublic road 230, “amount data” of the molten aluminum required for thestoring furnace 212, “temperature data”, and soon. In the second factory220, these data are displayed on the display section 222. Based on thesedisplayed data, the operator determines on his or her experiences thepoint of time for dispatch of the container 100 from the second factory220 and the temperature of the molten aluminum at the time of thedispatch so that the container 100 is delivered immediately to thestoring furnace 212 before the storing furnace 212 runs out of themolten aluminum and the molten aluminum at that time is at a desiredtemperature. Alternatively, the data may be downloaded into a computer(not shown) and using the predetermined software, the point of time fordispatch of the container 100 from the second factory 220 and thetemperature of the molten aluminum at the time of the dispatch so thatthe container 100 is delivered immediately to the storing furnace 212before the storing furnace 212 runs out of the molten aluminum and themolten aluminum at that time is at a desired temperature may beestimated and displayed. Alternatively, it is also adoptable toautomatically control the temperature of the second furnace 221 based onthe estimated temperature. It is also adoptable to determine the amountof the molten aluminum to be stored in the container 100 based on theaforementioned “amount data.”

When the truck 232 with the container 100 mounted thereon departs,passes the public road 230, and arrives at the first factory 210, thecontainer 100 is received from the truck 232 to the receiving station.

Then, the received container 100 is delivered by the transportingvehicle 1 to a predetermined die casting machine 211 so that the moltenaluminum is supplied from the container 100 to the storing furnace 212.

The present invention is not limited to each of the embodiment describedabove, however, can be used in many different format.

INDUSTRIAL AVAILABILITY

As explained above, according to the present invention, application ofpressure to the container can be stopped with more reliability, forexample, in an emergency, and with a very simple operation. In addition,the time consumed until the stop of the operation can be shortened,leading to improved safety.

In addition, according to the present invention, the pressure in thecontainer can steadily be increased without negatively affecting theoperability.

1. A pressure controlling apparatus for controlling a pressure in acontainer capable of storing a molten metal and supplying the moltenmetal to an outside using a pressure difference, comprising: a supplyingportion for supplying a compressed gas to be supplied to the container;a flow passage for supplying the compressed gas from the supplyingportion to the container; a first switching valve, being inserted intothe passage, capable of manually switching a first mode that enables thepassage of the gas between the supplying portion side and the containerside and a second mode that enables the passage of the gas between thecontainer side and the outside; an exhausting portion for exhausting agas from the container; and a second switching valve for switching apressure applying mode for applying a pressure to the container and anexhausting mode for exhausting the gas from the container, wherein theflow passage includes a first path for connecting the supplying portionand the second switching valve, a second path for connecting theexhausting portion and the second switching valve, and a third path forconnecting the second switching valve through to the container side, andwherein the first switching valve is inserted into the third path. 2.The pressure controlling apparatus as set forth in claim 1, wherein theswitching between the first mode and the second mode is performedexclusively with one same operation.
 3. The pressure controllingapparatus as set forth in claim 1, further comprising: at least one of aleak valve and a relief valve connected to the flow passage.
 4. Thepressure controlling apparatus as set forth in claim 3, wherein a partof the flow passage is an air tube having a connecting portion connectedto the container, and wherein a filter is inserted between the firstswitching valve and the connecting portion.
 5. The pressure controllingapparatus as set forth in claim 1, further comprising: a compressor,driven by an electricity generated by a generator, the generator beingdriven by an engine for driving a transporting vehicle for transportingthe container with the pressure controlling apparatus being mountedthereon; and a tank for storing the compressed gas compressed by thecompressor and supplied from the supplying portion.
 6. The pressurecontrolling apparatus as set forth in claim 1, further comprising: acompressor driven by an electricity of a battery for supplyingelectricity to a motor, the motor driving the transporting vehicle fortransporting the container with the pressure controlling apparatus beingmounted thereon; and a tank for storing the compressed gas beingcompressed by the compressor and being supplied from the supplyingportion.
 7. A transporting vehicle for transporting a container capableof storing a molten metal and supplying the molten metal to an outsideusing a pressure difference, comprising: an engine for driving thevehicle; a generator driven by the engine; a compressor driven by anelectricity generated by the generator; a tank for storing a compressedgas compressed by the compressor; and a pressure controlling portion,having an interface portion detachably disposed against the container,for applying a pressure in the container via the interface portion, thepressure control portion including a flow passage for supplying thecompressed gas from the compressor to the container a first switchingvalve, being inserted into the passage, capable of manually switching afirst mode that enables the passage of the gas between the compressorside and the container side and a second mode that enables the passageof the gas between the container side and the outside, an exhaustingportion for exhausting a gas from the container, and a second switchingvalve for switching a pressure applying mode for applying a pressure tothe container and an exhausting mode for exhausting the gas from thecontainer, the flow passage including a first path for connecting thecompressor and the second switching valve, a second path for connectingthe exhausting portion and the second switching valve, and a third pathfor connecting the second switching valve through to the container side,the first switching valve being inserted into the third path.
 8. Thetransporting vehicle as set forth in claim 7, further comprising: afilter disposed on a line connecting the compressor and the tank.
 9. Thetransporting vehicle as set forth in claim 7, wherein the container hasa hatch capable of being opened and closed on a top surface of thecontainer and the interface portion is detachably disposed against aconnecting portion on the hatch provided for controlling the pressure inthe container.
 10. A transporting vehicle for transporting a containercapable of storing a molten metal and supplying the molten metal to anoutside using a pressure difference, comprising: a motor for driving thevehicle; a battery for supplying an electricity to the motor; acompressor driven by the electricity in the battery; a tank for storinga compressed gas compressed by the compressor; and a pressurecontrolling portion, having an interface portion detachably disposedagainst the container, for applying a pressure in the container via theinterface portion, the pressure control portion including a flow passagefor supplying the compressed gas from the compressor to the container, afirst switching valve, being inserted into the passage, capable ofmanually switching a first mode that enables the passage of the gasbetween the compressor side and the container side and a second modethat enables the passage of the gas between the container side and theoutside, an exhausting portion for exhausting a gas from the container,and a second switching valve for switching a pressure applying mode forapplying a pressure to the container and an exhausting mode forexhausting the gas from the container, the flow passage including afirst path for connecting the compressor and the second switching valve,a second path for connecting the exhausting portion and the secondswitching valve, and a third path for connecting the second switchingvalve through to the container side, the first switching valve beinginserted into the third path.
 11. A transporting vehicle fortransporting a container capable of storing a molten metal and supplyingthe molten metal to an outside using a pressure difference, comprising:a compressor; a tank for storing a compressed gas compressed by thecompressor; an air tube, having an interface portion detachably disposedagainst the container on one end, and being connected through to thetank; a flow passage for supplying the compressed gas from thecompressor to the container, the flow passage having a line between thetank and the air tube, in which a gas flows; a first leak valveconnected to the line; and a filter disposed on the line and between thefirst leak valve and the interface portion; a first switching valve,being inserted into the passage, capable of manually switching a firstmode that enables the passage of the gas between the compressor side andthe container side and a second mode that enables the passage of the gasbetween the container side and the outside; an exhausting portion forexhausting a gas from the container: and a second switching valve forswitching a pressure applying mode for applying a pressure to thecontainer and an exhausting mode for exhausting the gas from thecontainer, the flow passage including a first path for connecting thecompressor and the second switching valve, a second path for connectingthe exhausting portion and the second switching valve, and a third pathfor connecting the second switching valve through to the container side,the first switching valve being inserted into the third path.
 12. Thetransporting vehicle as set forth in claim 11, further comprising: asecond leak valve disposed between the first leak valve and theinterface portion and connected to the line, wherein the filter isdisposed between the second leak valve and the interface portion and onthe line.
 13. A transporting vehicle for transporting a containercapable of storing a molten metal and supplying the molten metal to anoutside using a pressure difference, comprising: a compressor; a tankfor storing a compressed gas compressed by the compressor; a vacuumpump; an air tube, having an interface portion detachably disposedagainst the container on one end; a first switching portion capable ofmanually switching a first mode that enables the passage of the gasbetween the compressor side and the container side and a second modethat enables the passage of the gas between the container side and theoutside; a second switching portion; a first line becoming a flowpassage of a gas flowing between the tank and the second switchingportion; a second line becoming a flow passage of a gas flowing betweenthe vacuum pump and the second switching portion; and a third linebecoming a flow passage of a gas flowing between the second switchingportion and the air tube, wherein the first switching portion isinserted into the third line being inserted with a switching valve, andwherein the second switching portion switches a connection between thefirst line and the third line, and the connection between the secondline and the third line.
 14. The transporting vehicle as set forth inclaim 13, further comprising: a first leak valve disposed between thetank and the interface portion and on one of the first line and thethird line; and a filter disposed between the first leak valve and theinterface portion and on one of the first line and the third line. 15.The transporting vehicle as set forth in claim 14, further comprising: asecond leak valve disposed between the second switching portion and oneend of the air tube and connected to the third line, wherein the filteris disposed between the second leak valve and the air tube on the thirdline.
 16. A pressure difference controlling unit being mounted on atransporting vehicle, holding a container capable of storing a moltenmetal and supplying the molten metal to an outside using a pressuredifference, comprising: a compressor; a tank for storing a compressedgas compressed by the compressor; and a pressure controlling portion,having an interface portion detachably disposed against the container,for applying a pressure in the container via the interface portion withthe compressed gas, the pressure control portion including a flowpassage for supplying the compressed gas from the compressor to thecontainer, a first switching valve, being inserted into the passage,capable of manually switching a first mode that enables the passage ofthe gas between the compressor side and the container side and a secondmode that enables the passage of the gas between the container side andthe outside, an exhausting portion for exhausting a gas from thecontainer, and a second switching valve for switching a pressureapplying mode for applying a pressure to the container and an exhaustingmode for exhausting the gas from the container, the flow passageincluding a first path for connecting the compressor and the secondswitching valve, a second path for connecting the exhausting portion andthe second switching valve, and a third path for connecting the secondswitching valve through to the container side, the first switching valvebeing inserted into the third path.